Skip to:

Colorado's Questionable Use Of The Colorado Growth Model


I appreciate your analysis. One factor you may not have considered is the causal relationship between low SES and lower growth. School quality is the largest factor in student growth, but low SES students tend to have much less support at home. High SES parents tend to devote more resources to their childrens' education. If a high SES student is struggling in a subject, the parents are typically more able to assist with homework and even to find tutoring. A low SES parent is unlikely to have the same resources in time and money. Low SES parents are also likely to be less educated and may tend to value education less highly. This is one reason that median growth percentiles still trend with SES (even within the same school).

Matt, your comments seem to imply that if a model is *intended* to measure actual school or teacher effects, it's okay to use it for that purpose - otherwise it is not. Why does the CGM have "inferential issues" but other models don't? I think what you have in mind is a causal inference about performance, which is a separate issue from choice of a model, and at which all these models probably fail.

Tillie, You're correct that my wording seems to imply that, and it was not my intention. All the models are open to scrutiny as to whether they can support causal inference, at either the school- or teacher-level. I didn't want to get into that issue in this post, so I carelessly breezed through it. Thanks for helping me clarify. MD

It's not necessarily a problem that low performance on these metrics is correlated with low SES if we believe that low SES students are more likely to have low quality schools.


This web site and the information contained herein are provided as a service to those who are interested in the work of the Albert Shanker Institute (ASI). ASI makes no warranties, either express or implied, concerning the information contained on or linked from The visitor uses the information provided herein at his/her own risk. ASI, its officers, board members, agents, and employees specifically disclaim any and all liability from damages which may result from the utilization of the information provided herein. The content in the Shanker Blog may not necessarily reflect the views or official policy positions of ASI or any related entity or organization.